The invention relates to a drive line apparatus for use where there is limited space between a driving member and a driven member.
The drive line shaft connects the transmission output to the differential at the rear wheel on rear drive vehicles. The rotary motion of the transmission output shaft is carried to the differential and from there to the wheel. The drive line shaft must change in length and angle as the wheels move up and down. To allow for these two variations, two or more universal joints and a slip joint are required. The universal joint accommodates a change in the drive angle. The slip joint accommodates a change in the length of the drive line.
In the conventional drive line shaft, the slip joint has outside splines on one shaft and matching internal spines on a mating hollow shaft. The splines cause the two shafts to rotate together and to permit the two to move endwise in relation to each other. This allows changes in the length of the propeller shaft as the rear axles move toward or away from the vehicle frame.
Some vehicles, such as busses, have the engine mounted at the rear. Due to the limited space available, short shafts and universal joints carry the engine power to the rear wheels. It would be desirable to provide the shortest transmission shaft possible without sacrificing the strength of the shaft to support bearing stresses.
In one aspect of the invention, a drive line apparatus is provided for connection between an output portion of a driving member and an input portion of a driven member wherein the output portion and input portion are each connectible to a universal joint, and the drive line apparatus includes an outer hollow shaft connectible to a universal joint and an inner hollow shaft connectible to another universal joint wherein the outer and inner hollow shafts are telescopically connected so that at least a portion of the inner hollow shaft is disposed within the outer shaft and at least a portion of the universal joint connectible to the inner shaft is disposable within the inner hollow shaft to minimize the total length of the drive line apparatus.
In another aspect of the invention, a drive line apparatus is provided for connection between an output portion of the driving member and an input portion on the driven member wherein the drive line apparatus includes an outer hollow shaft having at least one open end and an inner hollow shaft having at least one open end. The drive line apparatus further includes means for rotating the inner hollow shaft in unison with the outer hollow shaft. The drive line apparatus further includes means for connecting either the inner or outer hollow shaft to the output portion of the driving member and means for connecting the other of the inner or outer hollow shaft to the input portion of the driven member, wherein at least a portion of the connection means to the inner hollow shaft is disposed within the inner hollow member.